code: def test_from_proto_to_json(self):
      model_card_proto = text_format.Parse(
          _FULL_PROTO, model_card_pb2.ModelCard()
      )
      model_card_py = model_card.ModelCard()
  
      # Use merge_from_proto.
      self.assertJsonEqual(
          _FULL_JSON,
          model_card_py.merge_from_proto(model_card_proto).to_json(),
      )
      # Use from_proto
      self.assertJsonEqual(
          _FULL_JSON,
          model_card.ModelCard.from_proto(model_card_proto).to_json(),
      )
  
imports: import json
  import os
  import pkgutil
  import jsonschema
  from absl.testing import absltest
  from google.protobuf import text_format
  from model_card_toolkit import model_card
  from model_card_toolkit.proto import model_card_pb2
label_desc: Use image node_id 15 for calling the ModelCardTest obj's underlying member method code with example usage: obj.test_from_proto_to_json() without return types